adding a reject reason to spam messages

Matt Kettler mkettler at EVI-INC.COM
Wed Dec 7 17:20:58 GMT 2005

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Erick Perez wrote:
> Well, if a legitimate user is sending a mail from an ip block that has
> been tagged as spam-generating (like an open-proxy that was later
> closed), i wanted to tell the user that his/her email was
> rejected/tagged as spam because it appeared in a spam/openproxy database.
> I've been in that position several times because one of the internet
> providers I use is being constantly entered into spam generating ip-blocks.
> When I was blocked i whised something will bouce back telling me why was
> not delivered instead of making me "think" it was delivered.
> ok, maybe not the user, but how about a forward to the postmaster of the
> offending domain with a copy of the message that triggered the reject?

Question: how do you know WHO to send the message to? How do you know the
appropriate postmaster for the IP address?

You certainly can't trust the From: Return-Path, or any other claimed email
address in the message. In the case of real spam these are forged.

This is why auto-bouncing spam notices is bad, real spam causes you to send
piles of mis-directed and completely useless notices to innocent third parties
who had their email address forged by a spammer.

I for one immediately blacklist sites that send such messages to my network. I
figure that any such server could at any moment flood my server with a large
deluge from a spam run.

A knowing spammer can intentionally abuse such a system as a method of DDoS
attack, using your server, and many others, as a flood-generating relay to shut
down networks.

Unfortunately, hand-reporting is the only way to go. This can't be done
automatically without creating an abusable flood-bot.

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